訪問: http://localhost:10086/mytomcat
MyTomcat/
└── src/└── com/└── zhang/├── MyServer.java├── MyRequest.java├── MyResponse.java├── MyMapping.java├── MyServlet.java└── MyHttpServlet.java
核心類功能說明
- MyServer.java
- 服務器主類,負責啟動并監聽端口(默認10086)
- 接受客戶端請求,創建 MyRequest 和 MyResponse 對象
- 根據URL映射找到對應的Servlet進行處理
-
MyRequest.java
- 請求處理類,解析HTTP請求中的方法(GET/POST)和URL
- 提供getter/setter方法訪問請求信息
-
MyResponse.java
- 響應處理類,構建HTTP響應
- 提供 write 方法發送HTML響應內容到客戶端
-
MyMapping.java
- URL映射配置類,維護URL到Servlet類的映射關系
- 目前配置了: /mytomcat -> com.zhang.MyServlet
- MyHttpServlet.java
- Servlet抽象基類,定義了處理GET和POST請求的抽象方法
- 提供 service 方法根據請求類型調用對應的處理方法
- MyServlet.java
- 具體的Servlet實現類,繼承自 MyHttpServlet
- 實現了 doGet 和 doPost 方法,返回不同的響應內容
工作流程
- 啟動服務器:運行 MyServer.main 方法,服務器在端口10086啟動
- 客戶端請求:當訪問 http://localhost:10086/mytomcat 時
- 請求解析: MyServer 創建 MyRequest 和 MyResponse 對象
- 映射查找:通過 MyMapping 找到對應的 MyServlet 類
- 請求處理:調用 MyServlet 的 service 方法,根據請求類型調用 doGet 或 doPost
- 響應發送: MyResponse 構建并發送HTTP響應到客戶端
訪問測試
- 可以通過瀏覽器訪問 http://localhost:10086/mytomcat 來測試GET請求
- 對于POST請求,可以使用curl或其他工具發送請求
這個簡單的Tomcat模擬實現了基本的HTTP請求處理和Servlet機制,展示了Web服務器的核心工作原理。
代碼
MyHttpServlet.java
package com.zhang;public abstract class MyHttpServlet {//定義常量public static final String METHOD_GET = "GET";public static final String METHOD_POST = "POST";public abstract void doGet(MyRequest request, MyResponse response) throws Exception;public abstract void doPost(MyRequest request, MyResponse response)throws Exception;/*** 根據請求方式來判斷使用那種處理方法** @param request* @param response*/public void service(MyRequest request, MyResponse response) throws Exception{if (METHOD_GET.equals(request.getRequestMethod())) {System.out.println(METHOD_GET + "請求");doGet(request, response);} else if (METHOD_POST.equals(request.getRequestMethod())) {System.out.println(METHOD_POST + "請求");doPost(request, response);}}
}
MyMapping
package com.zhang;import java.util.HashMap;public class MyMapping {public static HashMap<String, String> mapping = new HashMap<String, String>();static {
// http://localhost:10086/mytomcat 可以運行mapping.put("/mytomcat", "com.zhang.MyServlet");}public HashMap<String, String> getMapping() {return mapping;}
}
MyRequest
package com.zhang;import java.io.IOException;
import java.io.InputStream;/*** 請求對象*/
public class MyRequest {//請求方法 GET、POSTprivate String requestMethod;//請求地址private String requestUrl;//構造方法public MyRequest(InputStream inputStream) throws IOException {//緩沖空間byte[] buffer = new byte[1024];//讀取數據的長度int len = 0;//定義請求的變量String str = null;if ((len = inputStream.read(buffer)) > 0) {str = new String(buffer, 0, len);}//GET /HTTP /1.1String data=str.split("\n")[0];String [] params=data.split(" ");this.requestMethod=params[0];this.requestUrl=params[1];}public String getRequestMethod() {return requestMethod;}public void setRequestMethod(String requestMethod) {this.requestMethod = requestMethod;}public String getRequestUrl() {return requestUrl;}public void setRequestUrl(String requestUrl) {this.requestUrl = requestUrl;}
}
MyResponse
package com.zhang;import java.io.IOException;
import java.io.OutputStream;public class MyResponse {private OutputStream outputStream;//輸出public MyResponse(OutputStream outputStream) {this.outputStream = outputStream;}public void write(String str) throws IOException {StringBuilder builder = new StringBuilder();builder.append("Http/1.1 200 ok\n").append("Content-Type:text/html\n").append("<html>").append("<body>").append("<h1>" + str + "</h1>").append("</body>").append("</html>");this.outputStream.write(builder.toString().getBytes());this.outputStream.flush();this.outputStream.close();}
}
MyServer
package com.zhang;import java.io.InputStream;
import java.io.OutputStream;
import java.net.ServerSocket;
import java.net.Socket;public class MyServer {/*** 定義服務器的接受程序,接受socket請求** @param port*/public static void StartServer(int port) throws Exception {//定義服務端套接字ServerSocket serverSocket = new ServerSocket(port);//定義客戶端套接字Socket socket = null;while (true) {socket = serverSocket.accept();//獲取輸入流和輸出流InputStream inputStream = socket.getInputStream();OutputStream outputStream = socket.getOutputStream();//定義請求對象MyRequest request = new MyRequest(inputStream);MyResponse response = new MyResponse(outputStream);String clazz = new MyMapping().getMapping().get(request.getRequestUrl());if (clazz != null) {Class<MyServlet> myServletClass = (Class<MyServlet>) Class.forName(clazz);//根據myServletClass創建對象MyServlet myServlet = myServletClass.newInstance();myServlet.service(request, response);}}}public static void main(String[] args) {try {StartServer(10086);} catch (Exception e) {e.printStackTrace();}}
}
MyServlet
package com.zhang;public class MyServlet extends MyHttpServlet{@Overridepublic void doGet(MyRequest request, MyResponse response) throws Exception{response.write("get myTomcat 哈哈哈");}@Overridepublic void doPost(MyRequest request, MyResponse response)throws Exception {response.write("post myTomcat");}
}